JP2003148525A - Disk brake - Google Patents

Abstract

PROBLEM TO BE SOLVED: To smoothly retreat a pair of pads 6a and 6b from the both side surfaces of a rotor 1 by a pad return mechanism in releasing a brake irrelevant to the progress of abrasion of a lining. SOLUTION: Projecting pieces 17 and 17 are formed in a connecting part of a pad clip 14 provided between a support and the respective pads 6a and 6b. A pair of coil parts 23 and 23 provided in an intermediate part 19 of a return spring 18 clamp the projecting pieces 17 and 17 and support the intermediate part 19 in such a state as not to be deformed in the axial direction of the rotor 1 but deformed in the radial direction. This constitution can stabilize a force of pushing arm parts 20 and 20 of the return spring 18 pushing the respective pads 6a and 6b so as to solve the problem.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The disc brake according to the present invention is used for braking an automobile, and the present invention provides smooth pad return by a pad return mechanism accompanying brake release. , A disc brake that prevents friction between the pad lining and the side surface of the rotor during non-braking, reduces wheel rotation resistance during non-braking, and effectively prevents wear of the lining. is there.

[0002]

Disc brakes are commonly used for braking automobiles. An example of the structure and operation of such a disc brake will be described with reference to FIGS. 1 and 2 showing an embodiment of the present invention. In this disc brake, a support 2 provided adjacent to one side of a rotor 1 that rotates with wheels (not shown) is provided through mounting holes 3 provided at both ends in the circumferential direction near the inner diameter of the support 2. It is fixed to the vehicle body (actually a suspension device not shown). A caliper 4 is supported on the support 2 so as to be displaceable in the axial direction of the rotor 1 (front and back directions in FIG. 1, left and right directions in FIG. 2). Further, the pads 6a, 6 are provided on the engaging portions 5 provided at both ends in the circumferential direction of the rotor 1 as a part of the support 2.
Both ends of the back plate 7 forming b are engaged with the rotor 1 so as to be displaceable (sliding) in the axial direction. Further, the caliper 4 having the cylinder portion 8 and the caliper claw 9 is arranged in a state of straddling the both pads 6a and 6b, and the inner side (right side in FIG. 2) pad 6a is provided on the cylinder portion 8. A piston 10 for pressing against the rotor 1 is built in.

For braking, the cylinder portion 8 is used.
Pressure oil is sent into the inside, and the inner pad 6a on the inner side is pressed by the piston 10 against the inner surface of the rotor 1 from right to left in FIG. Then, as a reaction of this pressing force, the caliper 4 is displaced to the right in FIG. 2, and the caliper claw 9 is located on the outer side (left side in FIG. 2) of the pad 6b.
Are pressed against the outer surface of the rotor 1. As a result, the rotor 1 is strongly clamped from both inner and outer side surfaces, and braking is performed. Although not shown, a pair of pads are supported by a caliper fixed to the vehicle body, and a plurality of pistons provided in a state of facing the calipers press the pads toward the rotor. Disc brakes are also known from the past.

When the lining 11 of each of the pads 6a and 6b rubs against the side surface of the rotor 1 when the disc brake configured and acting as described above is not braked, the rotor 1
Not only does the torque (rotational resistance) required to rotate the wheel, which is fixedly connected, increases, but also the lining 11
Wears uselessly. The increase in rotational resistance causes deterioration of various performances of the automobile, such as fuel efficiency performance and acceleration performance. In addition, useless wear of the lining 11 causes a decrease in the traveling distance until the pads 6a and 6b are replaced, which increases operating costs.

Conventionally, in order to eliminate such inconvenience,
For example, as described in Japanese Patent Laid-Open No. 56-127830, a return spring is provided between the inner side pad and the outer side pad, and the friction surface of the linings of these pads is connected to the rotor when the braking is released. A structure is known in which it is separated from both sides. In the case of the conventional structure described in the above publication, both ends of the return spring are engaged with the locking holes formed at the ends of the back plate forming the pads. Further, the return spring is provided adjacent to the pad clip made of an elastic metal plate which is provided between the pads and the support and prevents the pads from rattling with respect to the support. And, by the stopper portion and the guide protrusion formed on this pad clip,
It is designed to prevent the return spring from falling off.

[0006]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the case of the conventional structure described in Japanese Patent No. 127830,
The pair of pads on the inner side and the outer side function as anchors for the return springs. Although the stopper portion and the guide projection are intended to prevent the return spring from coming off, they do not have a function as an anchor for bearing a reaction force caused by pressing the pads. On the other hand, the distance between the back plates for locking the locking portions provided at both ends of the return spring becomes shorter as the lining of each pad wears. Therefore, when the wear of the lining becomes uneven, the posture of the return spring is not always stable, and the force with which the return spring presses the pads is not always stable depending on the degree of wear of the lining. There are times when you don't. The present invention is
In consideration of such circumstances, the pad is not used as an anchor for the return spring, and the posture of the return spring is stabilized regardless of the degree of wear of the lining, so that the inner side pad and the outer side pad are lined when not braking. The invention was devised to realize a disc brake that can be reliably separated from the side surface of the rotor.

[0007]

DISCLOSURE OF THE INVENTION The disc brake of the present invention comprises a pad support member, a pair of pads, a pad clip, and a return spring, like the previously known disc brake. . The pad support member is fixed to the vehicle body adjacent to the rotor that rotates with the wheels, and supports the pair of pads so that the rotor can be displaced in the axial direction. Such a pad support member corresponds to a support in a floating caliper type disc brake or a caliper in an opposed piston type disc brake. The pair of pads are arranged opposite to both side surfaces of the rotor while being supported by the pad support member. or,
The pad clip is provided between the pads and the pad support member to prevent the pads from rattling with respect to the pad support member, and is made of an elastic material such as stainless spring steel plate. Is. The return spring is a spring material such as a torsion coil spring formed by winding a wire material made of stainless spring steel, and the two springs are connected to each other in a state of being suspended between the pair of pads. It has elasticity in the direction of widening the interval.

Particularly, in the disc brake of the present invention, the protruding piece is formed on a part of the pad clip.
An intermediate portion of the return spring is engaged with the projecting piece so that the rotor can be displaced in the radial direction while the axial displacement of the rotor is prevented. Further, preferably, as described in claim 2, the locking projections provided at both ends of the return spring are provided in the locking holes formed at the ends of the back plates of the pads, and the locking projections are provided on the rotor. Insert from the opposite side. A guide groove is formed on the end of the back plate facing the rotor at the outer peripheral edge of the back plate and reaching the locking hole.

[0009]

According to the disc brake of the present invention constructed as described above, the position of the intermediate portion of the return spring in the axial direction of the rotor remains constant regardless of the degree of wear of the lining of each pad. On the other hand, the position of the intermediate portion of the return spring in the radial direction of the rotor changes according to the degree of wear of the lining.
However, since the intermediate portion moves on the projection of the pad clip, the pad clip always functions as an anchor portion, and the pads can be stably separated from the side surface of the rotor.

[0010]

1 to 11 show a first example of an embodiment of the present invention. Since the basic structure and operation of the disc brake of the present invention are as described above,
Overlapping description will be omitted, and hereinafter, the characteristic part of the present invention and the part not described above will be mainly described. With respect to the circumferential direction of the rotor 1, the locking recesses 12 formed in the engaging portions 5 at both ends of the support 2 are provided with inner and outer pads 6a,
The pads 6a and 6b are supported so as to be displaceable in the axial direction of the rotor 1 by engaging the locking projections 13 provided at both ends of the back plate 7 which constitutes 6b. And
A pad clip 14 as shown in FIGS. 5 to 7 is interposed between each locking recess 12 and each locking projection 13. The basic structure and operation of the pad clip 14 are well known in the art. That is, the pad clip 14 is formed by bending a metal plate having elasticity and corrosion resistance, such as stainless spring steel and galvanized steel plate, and a pair of holding portions 15 provided at both ends. ,
15 are connected by a connecting portion 16.

The pad clips 14 are provided on the anchor side (the side that supports the brake torque) and the anti-anchor side of the disc brake, respectively. The holding portions 15 provided at both ends of each pad clip 14, 15 is
In each part, the inner side pad 6 and the outer side pad 6
It is sandwiched between the outer surface of the locking projection 13 provided at the ends of a and 6b and the inner surface of the locking recess 12 formed in the engaging portion 5 at the end of the support 2. Then, the locking projections 13 are elastically pressed in a predetermined direction to push the pads 6a, 6a.
b prevents the support 2 from rattling. or,
In this state, the connecting portion 16 is located radially outward of the outer peripheral edge of the rotor 1, and the pair of holding portions 15 and 15 are provided.
Connect each other.

Particularly, in the case of the pad clip 14 constituting the disc brake of the present invention, a part of the intermediate portion of the connecting portion 16 is bent and raised outward in the radial direction of the rotor 1, and a pair of protrusions are formed. The pieces 17, 17 are formed in a state of being separated from each other in the axial direction of the rotor 1. In addition, the bending and raising directions of the two protruding pieces 17, 17 do not necessarily have to coincide with the diametrical direction of the rotor 1. By bending and bending, the two protruding pieces 17, 17 project radially outward or the circumferential direction of the rotor 1 more than a part of the connecting portion 16 where the both protruding pieces 17, 17 are formed. Just do it. In any case, the distance between the two protruding pieces 17, 17 does not change in the plane direction of the connecting portion 16 (the two protruding pieces 17, 17 are parallel to each other in the plane direction).

The inner side and outer side pads 6 are also provided.
8 to 1 are provided between the end portions of the back plate 7 forming a and 6b.
A return spring 18 as shown in 1 is provided. The return spring 18 is a torsion coil spring formed by bending a wire material made of stainless spring steel, and is provided with pressure arms 20, 20 from both sides of an intermediate portion 19 provided at the center.
Has been extended. Of these, the intermediate portion 19 has U-shaped folded portions 22 at both ends of a U-shaped connecting portion 21,
The base end of 22 is continuous, and each of these folded-back portions 22,
The proximal ends of the coil portions 23, 23 are continuous with the distal end of 22. And, at the tips of these coil portions 23, 23,
The base ends of the pressing arms 20, 20 are continuous. Further, the tip ends of the pressing arms 20, 20 are bent in directions projecting in directions opposite to each other, and the locking projections 2 are respectively formed.
4 and 24.

Such a return spring 18 is shown in FIG.
As shown in FIGS. 4 to 4, the connecting portion 21 is disposed between the projecting pieces 17, 17 provided on the pad clip 14,
These projecting pieces 17, 1 are formed by the coil portions 23, 23 described above.
It is attached to the pad clip 14 in a state of sandwiching 7. Further, in this state, as shown in FIGS. 3 to 4, the locking projections 24, 24 are provided on the surfaces provided with the linings 11 in the locking holes 25 formed at the ends of the back plate 7. Insert from the opposite surface side. In this state, the pair of pressing arms 20, 20 forming the return spring 18 are in the state shown by the solid line in FIG.
The angle formed by 0 and 20 is smaller than that in the free state shown by the chain line α in the figure. Therefore, in this state, the inner side pad 6a and the outer side pad 6b are provided with elastic forces in the directions of separating from each other. In addition, each of the coil portions 23, 23
The intermediate portion 19 provided with is engaged with the projecting pieces 17, 17 of the pad clip 14 so that the rotor 1 can be displaced in the radial direction while being prevented from axial displacement of the rotor 1. It becomes a state.

According to the disc brake of the present embodiment constructed as described above, the intermediate portion 19 of the return spring 18 is provided.
The axial position of the rotor 1 remains constant regardless of the degree of wear of the lining 11 of the inner and outer pads 6a, 6b. On the contrary,
The position of the intermediate portion 19 in the radial direction of the rotor 1 changes depending on the degree of wear of the lining 11.
Therefore, the protrusions 17, 17 of the pad clip 14 are
The rotor 6 functions as an anchor portion that receives a force for separating the pads 6a and 6b from the side surface of the rotor 1.
The pads 6a and 6b can be stably separated from the side surfaces of the.

Lining 1 for each of these pads 6a, 6b
As the wear of No. 1 progresses, the distance between the back plates 7 of these pads 6a and 6b decreases. The angle formed by the pair of pressing arms 20, 20 forming the return spring 18 is smaller than the initial state shown by the solid line in FIG. 10 as shown by the chain line β in FIG. Even in this case,
With respect to the rotation direction of the rotor 1, the pressing arms 2
The positions of the locking projections 24 at the tip of 0 and 20 do not change.
The reason for this is that the locking projections 24 are
This is because it is still in the state of being inserted into the locking hole 25 formed at the end of the back plate 7 of 6b.

Therefore, as the wear of the lining 11 progresses, the intermediate portion 19 of the return spring 18 is
Along the locking projections 24, 24, the rotor 1 is moved radially outward from the state of the left half of FIG. 4 to the state of the right half of FIG. This movement is done smoothly.
In addition, before and after the movement and in the middle of the movement, the intermediate portion 19
However, without changing the position of the rotor 1 in the axial direction, the projecting pieces 17, 17 of the pad clip 14 serve as an anchor portion that receives a reaction force of the force for pressing the pads 6a, 6b. Side and continue to function independently of each other. As a result, the pads 6 are released as the brake is released.
The force for separating the friction surfaces of the linings 11a and 6a from the both side surfaces of the rotor 1 is stabilized, and it is possible to reliably prevent the two surfaces from rubbing against each other during non-braking.

Next, FIGS. 12 to 14 show a second example of the embodiment of the present invention, which corresponds to the second aspect. Similar to the case of the above-described first example in the case of this example, the locking projections 24 provided at both ends of the return spring 18 are attached to the pads 6 respectively.
The lining 11 is provided in the locking hole 25 formed in the locking projection 13 provided at the end of the back plate 7 of a (6b), and the lining 11 is inserted from the surface side facing the rotor. Particularly, in the case of this example, the guide groove 26 is formed on the end portion of the back plate 7 facing the rotor. This guide groove 26
Is open to the outer peripheral edge of the back plate 7, that is, the outer peripheral edge of the rotor in the peripheral edge of the locking projection 13, and reaches the locking hole 25. In other words, the locking projection 13 is formed with a guide groove 26 that opens to the outer peripheral edge side and reaches the central portion of the locking projection 13, and the locking hole 25 is formed in the inner part of the guide groove 26. is doing.

In the case of the structure of this example having such a guide groove 26, the work of engaging the locking projections 24 provided at both ends of the return spring 18 with the locking holes 25 can be easily performed. It That is, when the return spring 18 is bridged between the pair of pads 6a (6b),
As shown in FIG. 14, the locking projection 24 is attached to the guide groove 2.
The return spring 18 is pressed inward in the radial direction of the rotor (downward in FIG. 14) in a state in which the return spring 18 is inserted near the opening. By this work, with the locking projection 24 reaching the inner part of the guide groove 26, the locking projection 24
, But automatically enters the locking hole 25. Therefore, the work of mounting the return spring 18 can be easily performed.
In order to make such mounting work easier, it is preferable that the opening of the locking hole 25 on the guide groove 26 side is a slanted pot-shaped inclined surface 27.

[0020]

Since the disc brake of the present invention is constructed and operates as described above, each pad can be stably retracted from the side surface of the rotor after the braking is released, and the lining of each pad and the rotor It is possible to surely prevent the side surface of the vehicle from rubbing against each other, which contributes to improvement of running performance of the automobile and extension of the life of the pad.

[Brief description of drawings]

FIG. 1 is a partial front view showing a first example of an embodiment of the present invention as viewed from the outer side.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 BB of FIG. 1, shown without support.
Sectional view.

FIG. 4 is shown with a support and a caliper omitted,
The schematic diagram seen from the C arrow direction of FIG.

5 is a view of the pad clip taken out and viewed from the same direction as FIG. 3. FIG.

FIG. 6 is a diagram viewed from the right side of FIG.

FIG. 7 is a view seen from above in FIG.

FIG. 8 is a view of the return spring taken out and viewed from the same direction as FIG.

9 is a view on arrow D of FIG.

FIG. 10 is a view on arrow E of FIG.

FIG. 11 is a view on arrow F of FIG.

FIG. 12 is a view of the end portion of the pad viewed from the surface side provided with a lining.

13 is a cross-sectional view taken along line GG of FIG.

14 is a diagram showing a state where the end portion of the return spring is engaged with the end portion of the pad, as viewed from the left side of FIG.

[Explanation of symbols]

1 rotor 2 Support 3 mounting holes 4 calipers 5 Engagement part 6a, 6b pad 7 Back plate 8 Cylinder part 9 caliper claws 10 pistons 11 lining 12 Locking recess 13 Locking protrusion 14 Pad clip 15 Hugs 16 Connection 17 Protrusion 18 Return spring 19 Middle part 20 Pressing arm 21 Connection 22 Folding part 23 Coil part 24 Locking protrusion 25 locking hole 26 Guide groove 27 slope

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3J058 AA48 AA53 AA63 AA69 AA77                       AA83 AA87 BA41 BA55 CA47                       CA65 DD05 FA01

Claims (2)

[Claims] 1. A pad support member fixed to a vehicle body adjacent to a rotor that rotates together with a wheel, and a pair of pads arranged to face both side surfaces of the rotor while being supported by the pad support member. A pad clip made of an elastic material, which is provided between each pad and the pad support member to prevent the pad from rattling with respect to the pad support member, and is bridged between the pair of pads. Also, in a disc brake provided with a return spring having elasticity in a direction of increasing the distance between these pads, a protrusion is formed on a part of the pad clip, and the return spring of the return spring is attached to the protrusion. A disc brake, wherein an intermediate portion is engaged with the rotor so that the rotor can be displaced in the radial direction while preventing the axial displacement of the rotor. 2. Locking protrusions provided at both ends of the return spring are inserted into locking holes formed at the ends of the back plates of the pads from the surface side facing the rotor. The disc brake according to claim 1, wherein a guide groove is formed at an end of the back plate facing the rotor, the guide groove opening to an outer peripheral edge of the back plate and reaching the locking hole portion. .